Benzyl-n-(n-butyl) chlorophenoxythiobutyrimidates

ABSTRACT

Benzyl-N-(n-butyl)-chlorophenoxythiobutyrimidates are prepared by reacting N-(n-butyl)-di- or trichloro-phenoxythiobutyramide with benzyl bromide in the presence of sodium alkylate. The compounds are useful as herbicides.

Q Umted States Patent 1 1 1111 3,725,452 Rumanowski 1 Apr. 3, 1973 [54] BENZYL-N-(N-BUTYL) [56] References Cited gs igfigg gg UNITED STATES PATENTS 3,268,539 8/1966 Levy ..260/453 R [75] Inventor Edmund Ruma'wwsk" Denver 2,412,510 12 1946 Jones ..71 9s 2,811,526 10/1957 Burtner ..260/453 R [73] Assignee: Allied Chemical Corporation, New FOREIGN PATENTS R APPLICATIONS,

York 39,645 5/1964 Belgium 71/98 22 Filed: Aug. 9, 1971 [21] Appl. No.: 170,354 Primary Examiner-Lewis Gotts Assistant Examiner-G. 'Hollrach Related US. Application Data Atmmerdohn Lipari [62] Division of Ser. No. 863,011, Sept. 24, 1969, Pat.

.No. 3,628,944. [57] ABSTRACT [52] U S Cl 260/453! 260/55 R Benzyl-N-(n-butyl)-chlorophenoxythiobutyrimidates [5 I] "607: 9/20 are prepared by reacting N-(n-butyl)-dior trichloro- [58] Fieid ..260/453 R;7l/98 Phenmythiobmyramide with benzyl bromide in the presence of sodium alkylate. The compounds are useful as herbicides.

3 Claims, No Drawings 1 BENZYL-N-(N-BUTYL) CHLOROPHENOXYTHIOBUTYRIMIDATES This is a division of application Ser. No. 863,011 filed Sept. 24, 1969 now US. Pat. No. 3,628,944.

BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION The novel compounds of the instant invention are diand trichlorophenoxythiobutyrimidates of the formula:

wherein R is hydrogen or chlorine.

The compounds are prepared by reacting N-(n-butyl)-dior trichlorophenoxythiobutyramides with benzyl bromide to form the corresponding benzyl-N- (n-butyl)-dior trichlorophenoxythiobutyrimidates. The novel compounds are useful as herbicides.

DETAILED DESCRIPTION OF THE INVENTION The novel compounds of the present invention are normally prepared by reacting N-(n-butyl)chlorophenoxythiobutyramide with benzyl bromide in the presence of an equivalent amount of sodium methylate, according to the following sequence:

with alcoholic solution of ammonia and hydrogen sulfide [Blank, Berichte, 25, 3043 (1892)]. Benzyl bromide is available commercially. The corresponding N- (n-butyl)-chlorophenoxythiobutyramides may be prepared by reacting the thiobutyramides with n-butylamine.

The instant compounds have been found to be unexpectedly effective herbicides in that they are very harmful to plants normally considered undesirable,

such as rape and broadleafed weeds, while being harmless toward com. Benzyl-N-(n-butyl)-2,4- dichlorophenoxythiobutyrimidate is the preferred compound for this purpose.

Normally, the instant compounds are used asthe active ingredient in a herbicidal composition, although they may also be used without a carrier. Various diluents and carriers may be employed and the percent of active ingredient may be varied. Although compositions with less than about 0.5 percent by weight of active ingredient may be used, it is preferable to use compositions containing at least about 1.0 percent of active ingredient, since otherwise the amount of carrier becomes excessively large. Activity increases with the concentration of active ingredient, which may be 10,

50, 95 percent or even higher.

The amount of composition which is applied for effective herbicidal action is dependent upon considerations such as the type of undesirable plant to be killed,

the density of undesirable plants, and soil and climatic conditions. Usually, sufficient composition may be applied to provide about 8 to 16 pounds of active ingredient per acre.

The instant herbicidal compositions may be in the form of a solution, with the solvent being selected from acetone, methylene chloride, and the like. The solutions can be applied to the plants in a direct manner such as by spraying, sprinkling, drenching, etc. Water suspensions can also be applied in this manner, with dispersing and emulsifying agents such as sodium alkyl sulfates and sulfonates and the like.

Application of the composition can also be achieved wherein R is hydrogen or chlorine.

Approximately equimolar amounts of the two substrates are used, although an excess of benzyl bromide is preferably used to achieve a higher yield with respect to the other substrates. The reaction may be conducted without use of an inert solvent, although it is more convenient to use a solvent such as methanol or ethanol. Preferably, the reaction is conducted at a temperature within the range of about 35 to 70C. Reaction times as short as about one-half hour or less have been found to be adequate, although longer reaction times .may be used, if desired. Atmospheric pressure is normally used for the reaction.

Substrate materials are available by procedures taught in the prior art. For example, the various chlorophenoxythiobutyramides may be prepared byreacting the appropriate chlorophenoxybutyronitrile by dusting a powder in which the. active ingredient is dispersed. Suitable carriers include finely powdered 55 material such as clays, fullers earth, talc, etc.

limiting the scope of the instant invention, which is defined by the appended claims.

' EXAMPLE I Preparation of Benzyl-N-( n-Butyl)-2,4- Dichlorophenoxythiobutyrimidate Sixteen grams of N-(n-butyl)-2,4-dichlorophenoxythiobutyramide and 9.4 grams of benzyl bromide were mixed in a lOO-ml 3-necked flask containing 60 ml ab solute ethanol. The flask was titted with a reflux condenser, stirrer, and a thermometer. About 3 grams of sodium methylate in 20 ml absolute ethanol were then added slowly with stirring to the mixture over a period of to minutes. The temperature was maintained between 45 to 50C. during the addition of the sodium methylate. The mixture was then heated at 45 to 55C. with stirring for another 30 minutes. Water was then added to the mixture and the solution was extracted with l00 ml of methylene chloride. The extract was washed with water and dried over anhydrous magnesium sulfate. The solvent was then stripped.

Yield: 18 grams of viscous oil Analysis Calculated Found %C: 62.8 63.0 %H: 6.2 7.l

EXAMPLE II The procedure of Example I was repeated using an equivalent amount of appropriate dior EXAMPLE Ill Herbicidal Activity The following crop species and weed species were planted in metal flats (12 X 8.5 X 4 inches) in greenhouse potting soil containing one-third mixed clay and sand, one-third mushroom soil, and one-third peat moss. The pH of the soil was 6.8 to 7.2. Crop Species Corn, Zea mays, Hybrid US 13 Wheat, Triticum vulgare, variety Thorne aluminum trays and were irrigated until the surface of v the soil in the flat was uniformly moist (at field capacity). Additional subirrigation was provided as needed to maintain moisture. No surface irrigation was applied,

The flats were sprayed eight to en days after seeding in the postemergence tests. Results were observed fourteen days after spraying.

The effect of the herbicide was evaluated in terms of the injury rating index scale, ranging from 0 to 10 as follows:

0 No apparent injury 1,2,3 Slight injury 4,5,6 Moderate injury 7,8,9 Severe injury (plants will die) 10 Plants were dead An injury rating of 3 is the maximum tolerated for crops and a rating of 7 is the minimum acceptable on weed plants.

Injury Rating at 16 Pounds Per Acre Plant Postemergence Com 1 Cotton 10 Wheat 4 Soybean l0 Rape 10 I claim:

1. Compound of the formula:

wherein R is hydrogen or chlorine.

2. Compound of claim 1 wherein R is hydrogem 3. A compound of claim 1 which is benzyl-N-(n-butyl)-2,4-dichlorophenoxythiobutyrimidate.

* III III t t 

2. Compound of claim 1 wherein R is hydrogen.
 3. A compound of claim 1 which is benzyl-N-(n-butyl)-2,4-dichlorophenoxythiobutyrimidate. 